Deburring tool



Jan. 26, 1965 s. A. COGSDILL DEBURRING TOOL Filed Aug. 10. 1961 m H M y \NN R E 52 2/4/2 f7. [a gsJZZ NN H H &

United States Patent Ofifice 3,156fi58 Patented Jan. 26, 1965 3,166,958 DEBURRING TOOL Stuart A. Cogsdill, Orchard Lake, Mich, assignor to Cogsdill Tool Products, Inc., Detroit, Mich, a corporation of Michigan Filed Aug. 10, 1961, Ser. No. 130,583 4 Claims. (Cl. 77-735) This invention relates to deburring tools and particularly a deburring tool having a blade for removing the burr from one or both sides of an aperture.

The present invention pertains to a deburring tool which is of simple and rugged construction having a cylindrical body portion of a diameter to fit an aperture or which may have a forward end substantially smaller than the spring containing driving end for deburring apertures of small diameter. The cylindrical body of the deburring tool has a diametrically disposed slot extending inwardly therein-to which is disposed therein from a point inwardly of the end for the greater part of the length of the body to the driving end thereof. At the forward end of the body, a slot is machined on the opposite side thereof in continuation of the first slot to have it disposed completely through the body at the front end thereof.

A flat blade has an outwardly extending truncated triangular cutting nib at the forward end and a notch at the rear end on the top side of the blade. The blade has two sloping rear edges which forms a fulcrum point at the point of engagement. A longitudinally extending spring has projecting fingers at each end one of which extends into an aperture in the notched portion of the blade and the other into an aperture at the rear end of the slot. A threaded aperture bisects the slot and extends inwardly near the rear end thereof for receiving a set screw which engages the top edge of the springintermediate its ends. The spring retains a set screw in a juxtaposition and applies a desired pressure to the spring which may be increased or decreased. The set screw has crossed slots in the inner end which mate with the top of the spring to thereby form a lock to prevent the set screw from turning after adjustment. A flat surface is provided in the forward end of the body in communication with the slot adjacent to the cutting nib to form a chip breaking and receiving recess.

Accordingly, the main objects of the invention are to provide a deburring tool having a cylindrical body containing a slot in which a blade is mounted to rock on a point on the rear edge thereof and retained in extended cutting position by a spring disposed in extension thereof; to provide a blade which is rockable within a slot in the body of a deburring tool with an outwardly projecting nib at one end and with a spring at the other for urging the nib outwardly of the slot with a predetermined pressure, to mount a rockable blade and a spring disposed extension thereof within a slot in a body containing a set screw in engagement with the spring which changes the force exerted thereby when adjusted; to provide projections on the end of an adjustable set screw for varying the tension of a spring which is locked in adjusted position by the projection thereof; to provide a tool for deburring a small hole having a body portion having a forwardly extending reduced end portion containing a slot disposed in alignment with the bottom of the slot in the main body portion in which a blade is pivoted and urged outwardly by a spring disposed in tension thereof, and in general, to provide a deburring tool which is simple in construction, positive in operation, and economical of manufacture.

Other objects and features of the novelty of the invention will be specifically pointed out or will become apparent when referring, for a better understanding of the invention, to the following description taken in conjunction with the accompanying drawing, wherein:

FIGURE 1 is a top plan view of a deburring tool embodying features of the present invention;

FIG. 2 is a side view of the tool illustrated in FIG. 1;

FIG. 3 is an enlarged broken sectional view of the tool illustrated in FIG. 1, taken on the line 3-3 thereof;

FIG. 4 is a sectional view of the structure illustrated in FIG. 1, taken on the line 4-4 thereof;

FIG. 5 is a sectional view of the structure illustrated in FIG. 3, taken on the line 5-5 thereof, and

FIG. 6 is a view of a tool similarly illustrated in FIG. 1, showing another form thereof.

The deburring tool of the present invention comprises a body 7 of cylindrical construction having a longitudinal slot 8 cut therein on a diameter leaving a thin bottom wall. The slot extends from the collet engaging portion to a point inwardly from the front end. The forward end of the body has a cutout portion 9 disposed inwardly from the opposite side from the slot 8 in communication therewith. A threaded aperture 11 extends downwardly into the slot 3 on the center thereof and is provided with a threaded screw 12. The rear end of the slot has an aperture 13 and a cutaway portion 14 adja-. cent to the front end of the slot forms a chip clearing area.

A blade 15 is made of flat stock to fit within the slot 8 and is formed to have an extending nib 16 at the top front end thereof. The nib has a forward cutting edge 17 and a rearward cutting edge 18, for cutting a burr at the forward face of an aperture when the end of the tool is advanced therein and for cutting the burr on the rear face of the aperture through a plate when the tool is retracted into aperture as it is being withdrawn therefrom. The top of the nib 19 between the cutting edges 17 and 18 is of arcuate shape both laterally and longitudinally of its top surface.

The forward rear edge portion 21 of the blade slopes upwardly and is disposed at an angle to the rear edge portion 22 at the rear of the blade. A fulcrum point 23 is formed at the point where the edges meet portions 21 and 22. The top edge 24 of the blade is parallel with the top of the slot when the rear edge portion 22 engages the bottom of the slot 3 and in this position the nib 16 extends a maximum amount from the body. The rear edge of the blade is notched at 25 and provided with a recess 26 in which a finger 27 of a spring 23 extends. A finger 29 at the opposite end of the spring extends into an aperture 31 in the rear bottom portion of the slot 8. After the spring is assembled on the blade the set screw 12 is advanced within the threaded aperture 11 into engagement with the spring 28. The set screw applies a force to the spring which is transferred by the finger 27 to the rear end of the blade to force the nib 16 from the slot 8 and apply cutting pressure thereto while permitting it to pass through the aperture from which the burr is being machined. The amount of spring pressure may be changed from time to time depending upon the material of the workpiece or weakness occurring to the spring 28.

The threaded screw 12 has a plurality of slots 32 on the inner end thereof which engages a portion 33 of the spring which may be machined Ito fit the slots. This prevents the threaded screw 12 from turning after it has been adjusted to apply the pressure to the spring. The pressure in the spring urging it into the slot locks the screw from rotation.

In FIG. 6 the tool is illustrated similar to that of FIGS. 1 to 5 with the exception that the forward body portion 34 in extension of a rear body portion 35 is of reduced diameter for deburring small apertures. The rear body portion 35 is of a diameter to fit a driving tool and to have sufficient area for the spring 28 Which urges the rear edge portion 22 of the blade 15 into the bottom of the slot which is aligned with the bottom edge of the front body portion 34. Otherwise, the tool is the same as that hereinabove described with regards to FIGS. 1 to 5, inclusive.

What is claimed is:

1. In a deburring tool, a cylindrical body having a diametrical slot closed at the bottom extending inwardly from one side thereof, a blade within said slot having a cutting edge extending outwardly at one end and having mating sloping surfaces at the opposite edge forming a fulcrum point which engages the bottom of the slot to rock thereon, a spring within said slot having one end in engagement with the rear end of the blade and the opposite end in engagement with the body, said engagement being such as to lock the spring with the body and the blade against longitudinal separation, said body having a threaded aperture therein in the area of said spring, and a threaded screw within said slot engaging the spring, the forward cutting end of said tool being of less diamerter than the diameter of the rearward driven end thereof.

2. In a deburring tool, a cylindrical body having a slot with a bottom, a blade within the slot having an edge engagement with the bottom upon which it is rocked, a spring within the slot in extension of the blade, said spring having one end in engagement with the innermost end of the blade and the other end in engagement with the body within the slot, the engagement being such as .to lock the spring with the body and the blade against spring having one end in engagement with the innermost end of the blade and the other end in engagement with the body within the slot, the engagement being such as to lock the spring with the body and the blade against longitudinal separation, an adjusting screw engaging the spring interjacent the ends thereof, and projections on the end of the screw in engagement with the spring which prevents the screw from turning after adjustment.

4. In a deburring tool, a cylindrical body having a slot with a bottom extending inward on the diameter thereof from one side of the body, an elongated blade within the slot having a cutting nib on one end extending from one edge of the blade, the opposite edge being shaped to have a fulcrum point in engagement with the bottom of the slot, a spring in extension of said blade having one end in engagement with the inner end of the blade and the other end in engagement with the body within the slot, the engagement being such as to lock the spring with the body and the blade against longitudinal separation, and means for applying a pressure between the ends of the spring for rocking the blade and extending the cutting nib thereof outwardly of the body.

References Cited in the file of this patent UNITED STATES PATENTS 2,314,084 Fried Mar. 16, 1943 2,373,474 Heyer Apr. 10, 1945 2,437,822 Jones Mar. 16, 1948 2,438,558 Hollander Mar. 30, 1948 2,739,497 Fried Mar. 27, 1956 2,878,696 Busch Mar. 24, 1959 2,895,356 Cogsdill July 21, 1959 FOREIGN PATENTS 22,861 France Mar. 10, 1921 (1st addition to 519,174) 44,334 France Oct. 1, 1934 

1. IN A DEBURRING TOOL, A CYLINDRICAL BODY HAVING A DIAMETRICAL SLOT CLOSED AT THE BOTTOM EXTENDING INWARDLY FROM ONE SIDE THEREOF, A BLADE WITHIN SAID SLOT HAVING A CUTTING EDGE EXTENDING OUTWARDLY AT ONE END AND HAVING MATING SLOPING SURFACES AT THE OPPOSITE EDGE FORMINGG A FULCRUM POINT WHICH ENGAGES THE BOTTOM OF THE SLOT TO ROCK THEREON, A SPRING WITHIN SAID SLOT HAVING ONE END IN ENGAGEMENT WITH THE REAR END OF THE BLADE AND THE OPPOSITE END IN ENGAGEMENT WITH THE BODY, SAID ENGAGEMENT BEING SUCH AS TO LOCK THE SPRING WITH THE BODY AND THE BLADE AGAINST LONGITUDINAL SEPARATION, SAID BODY HAVING A THREADED APERTURE THEREIN IN THE AREA OF SAID SPRING, AND A THREADED SCREW WITHIN SID SLOT ENGAGING THE SPRING, THE FORWARD CUTTING END OF SAID TOOL BEING OF LESS DIAMETER THAN THE DIAMETER OF THE REARWARD DRIVEN END THEREOF. 